Triple valve for air-brake systems.



No. 773,043. v PAT-ENTED OCT. 25, 1904';

' .w-. v. TURNER. S

TRIPLBNVALVB FOR AIR BRAKE SYSTEMS. APPLICATION FILED JAN. 2. 1903.

N0 MODEL.

1647166566 Q I I Ira 67250 7" V UN TED STATES Patented October 25, 1904,

PATENT OFFICE.

WALTER V. TURNER, OF TOPEKA, KANSAS, ASSIGNOR TO THE W'ESTING- HOUSE AIRBRAKE COMPANY OF PITTSBURG, PENNSYLVANIA, A COR- PORATION OFPENNSYLVANIA.

TRIPLE VALVE FOR AIR-BRAKE SYSTEMS.

I SPECIFICATION forming part of Letters Patent No. 773,043, datedOctober 25, 1904.

Application filedJanuary 2, 1903.

To a whom it may concern.-

Be it known that .L'WALTER V. TURNER, a citizen of the United States,residing at T0- peka, in the county of Shawnee and State of 5 Kansas,have invented certain new and useful Improvements in Triple Valves forAir-Brake Systems,of which the following is a specification. 7

This invention relates to triple-valve devices I for air-brakes, andmore particularly to that class known as quick-action triple valves,wherein a local venting of the train-pipe occurs at each triple valve inemergency applications of the brakes. In the present stand- I 5 ardtriple-valve devices of this type, as is well 1 known, the main triplepiston moves in response to a gradual reduction of train-pipe pressureto an intermediate position, known as service position, in whichcommunica- 2 tion is established from the auxiliary reservoir to thebrake-cylinder, and in this positionv the stem of the piston touches thestem of the graduating-spring, which tends to prevent further rearwardmovement of the piston. In

2 5 emergency applications, however,.the piston is moved by asuddenreduction of train-pipe pressure to the extreme endof itstraverse, compressing the graduating-spring and seating itself againstthe usual gasket at the rear end of 3 the piston-chamber. When seated inthis position, the elfective area of the piston exposed to train-pipepressure is reduced to the extent of the surface engaging the gasket.Consequently when it is desired to releasethe 35 brakes after anemergency application or after a full service application, in which thetrainpipe pressure is reduced below the equalized pressure of theauxiliary reservoir and brakecylinder, it is not only necessary to raisethe r 4 train-pipe pressure to equal that of the auxil- 45 thetrain-pipe side and-force the same away SerialNp. 137,553. (NomodeL)cations, due to a bursted hose or other accidentin which the train-pipeis emptied to the atmosphere, in order to prevent the leakage of theair-pressure from the auxiliary reservoir to the train-pipe, still inordinary emergency applications this diminishing of the effective areaof the train-pipe face of the piston by its engagement with the gasketcauses a delay in the release of the brakes, which is at times quiteobjectionable.

The principal object of this invention is the provision of supplementalmeans, such as a spring, tending to resistlthe final part of themovement of the triple piston to its emergency position against thegasket and acting to assist thetrain-pipe pressure and graduating springto overcome the opposing auxiliary-reservoir pressure and move thepiston away from the gasket when it is desired to release the brakes.When a recharging device is employed for recharging the auxiliaryreservoir from the train-pipe while the brakes remain applied andwithout moving the triple valve to release position, it is desirable tohave the recharging-passage connected to the piston chamber just at the7 rear of the normal lap position of the triple standard triple-valvestructure it is impossible to recharge the auxiliary reservoirs after anemergency application without releasing the brakes, for the reason thatas soon as the train-pipe pressure is increased sufficiently to move thepiston away from its gasket it pre' dominates over theauxiliary-reservoir pressure by several pounds and immediately carriesthe piston to release position.

By means of my improvement, in which the triple piston is moved awayfrom its seat/ against the gasket when the train-pipe pressure issubstantially equal to that of the auxiliary reservoir, the usualgraduating-spring assists in moving the piston to lap position only, andthere it may be stopped, while the recharging-port is opened, and theauxiliary reservoir may then be recharged by a very slow feeding of airto the train-pipe without moving the triple valve to release position,the release being effected by the usual increase of train-pipe pressurewhenever desired.

In the accompanying drawings, Figure 1 is an elevation, partly insection, showing a quick-action triple valve constructed and arranged inaccordance .with these improvements and With the parts in what is knownas lap position; and Fig. 2, a detail thereof with the parts arranged inemergency position.

In constructing a quick-action triple valve in accordance with theseimprovements I use a valve-body 2, in which are seated the usualwell-known slide and graduating valves. Attached to and forming a partof the valve body is a cylinder 3, provided with a cylinder-chamber, inwhich the main piston 4 operates.

To control the admission of air under pressure to the auxiliaryreservoir through pipe 5 and from the auxiliary reservoir to thebrake-cylinder 6, the slide and graduating valves, above alluded to, arearranged in the usual and well-known manner and need no furtherillustration or description here further than to say that the air underpressure passes around the main piston when the parts are in "releaseposition by means of the usual feed-grooves 2' and c and into theauxiliary reservoir by means of the pipe 5, from whence it is drawn asneeded for use in the brake-cylinder 6.

It is Well known in this art that when the engineer gradually reducesthe train pipe pressure the superior pressure on the auxiliary reservoirside of the main piston causes it to be moved until the service-port isopened from the auxiliary reservoir to the brake-cylinder and the stem jencounters the graduating-stem 7, which, through the resistance of itsgraduatingspring 8, prevents further movement thereof and holds theparts at what is known as service position; but when a sudden reductionof train-pipe pressure is had the superior pressure on theauxiliaryreservoir side of such main piston causes it to be moved soquickly that it compresses the graduating-spring, so that such pistonmoves to emergency position, as shown in Fig. 2, In this position thetrain-pipe side of the main piston is seated against the cylinder-capgasket 9, which reduces the effective area of such side of the piston,and thereby requires a considerable increase of the train-pipe pressureabove that of the auxiliary reservoir when it is desired to release. Inorder to facilitate the release movement of the triple piston and Valve,a supplementary spring 10 is provided,

coiled about the primary grzuluating-spring and interposed between ashouldered sleeve 11 and the graduating-screw 12 of the cylinder-cap 13.

A recharging device, which may be of any desired construction, isindicated at 15 and communicates by a port 16 with the pistonchamber ata point in the rear of the lap position of the piston and is alsoadapted to communicate with the auxiliary reservoir by means of a pipe17.

An examination of the drawings in connection with the foregoingdescription will show that the main piston may be moved, as heretofore,to emergency position without encountering any increased resistanceuntil just as it reaches the limit of motion in that direction, when theshoulder 14; of the graduatingstem engages the shouldered sleeve and thesupplementary graduating-s awng is brought into action to compensate forthe reduction of the superficial area of the train-pipe side of suchpiston.

The supplemental spring is preferably made of such strength as tosubstantially compensate for diminished area of the piston exposed totrain-pipe pressure, so that in order to release the brakes after anemergency application it will only be necessary to raise the train-pipepressure to substantially equal that of the auxiliary reservoir, whenthe piston will be moved away from the gasket. If the trainpipe pressureis then raised very slowly, the triple piston will be moved by thegraduating-spring only to lap position, where it will stop, with therecharging-passage 16 open, and the auxiliary reservoir may then berecharged to any extent desired without releasing the brakes; but if itis desired to release immediately the train-pipe pressure will beincreased more rapidly, as in the usual way, and the triple valve willbe forced all the way over to release position.

From the foregoing description it will now be apparent that by means ofmy improvement the brakes may be readily released after an emergencyapplication, or, if desired, a

' recharging of the auxiliary reservoir may be had without moving thetriple valve to release position.

Having now described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

1. A triple-valve device, comprising a main piston, means fordiminishing the effective area thereof exposed to train-pipe pressurewhen in emergency position, and supple mental means acting to assist thetrain-pipe pressure in moving the piston from its emergency position.

2. A triple-valve device, comprising a main piston subject to theopposing pressures of the auxiliary reservoir and trainnpe, means fordiminishing the effective train-pipe area of the piston in its emergencyposition, and

a spring acting only in emergency position to assist the trainpipepressure in moving the piston in opposition to the auxiliary-reservoirpressure.

position, a gasket forming a seat for the piston in its emergencyposition, and a supplemental spring acting upon the piston when in itsemergency position to assist the train pipe pressure in moving thepiston away from the gasket.

5. A triple-valve device, comprising a main piston subject to theopposing pressures of the auxiliary reservoir and train-pipe, a gas' vket forming aseatfor said piston in its emergency position, and asupplemental spring acting only in.emergency position to assist thetrain-pipe pressure in moving the piston in opposition to theauxiliary-reservoir pressure. p v 6: A triple-valve device, comprising amain piston subject to the opposing pressures of the auxiliary reservoirand train-pipe, a gas ket forming a seat for said piston in emergencyposition, a recharging-passage for the auxiliary reservoir leading fromthe pistonchamber between lap position and emergency position, and asupplemental spring acting on said piston in emergency position.

7. In a triple-valve-of the class described, the combination of avalve-body and cylinder, a main piston movably mounted in such cylinderand responsive to variations of fluidpressure in the train-pipe formoving the usual valve mechanism in the valve-body into and out ofposition to cause the operation of the brake mechanism, a cylinder-capattached to the cylinder, a graduating-screw in the same, agraduating-stem havinga shouldered inner end, a primary helically-coiledgraduating-spring between the graduating stem and screw to form aninitial yielding stop for the scribed.

WALTER V. TURNER.

Witnesses:

R. J. HOWARD, A. M. WARNER.

